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Re: NTY compression proposal (fwd)
All editing errors are my own, I re-formatted the original text to better
address the points.
> Date: Sun, 18 Jan 1998 19:17:32 -0800
> From: Steve Schear <[email protected]>
> Subject: Re: NTY compression proposal
> Compression efficiency depends upon
> 1) the entropy of the input data
We are looking at selecting 100 64-bit keys out of a set of 2^64,
that is not a lot of opportunity there, given a random key generation
process, for a lot of commen patterns in the key set. If we don't have a
lot of commen patterns in the text we don't get a lot of compression.
> 2) the allowable losses
In this case we can't afford any loss.
> 3) finding an efficient algorithm to code for that entropy.
Which if we do the math requires something in the neighborhood of 33:1,
for a loss-less algorithm that's a pretty hurky boundary condition.
> I think I'm on fairly firm ground assuming that key data entropy is very=
> high and therefore little or no compressible is feasible.
My point exactly, which would lead us to the conclusion that our requirement
of a 33:1 compression factor is not realizable.
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